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<title>user/sven/linux.git/kernel/sched_features.h, branch v3.2.79</title>
<subtitle>Linux Kernel
</subtitle>
<id>https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v3.2.79</id>
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<updated>2011-11-14T11:50:40Z</updated>
<entry>
<title>sched, rt: Provide means of disabling cross-cpu bandwidth sharing</title>
<updated>2011-11-14T11:50:40Z</updated>
<author>
<name>Peter Zijlstra</name>
<email>a.p.zijlstra@chello.nl</email>
</author>
<published>2011-10-06T20:39:14Z</published>
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<id>urn:sha1:4a6184ce7a48c478dee0d8a9ed74c1fa35161858</id>
<content type='text'>
Normally the RT bandwidth scheme will share bandwidth across the
entire root_domain. However sometimes its convenient to disable this
sharing for debug purposes. Provide a simple feature switch to this
end.

Signed-off-by: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
</content>
</entry>
<entry>
<title>sched: Kill WAKEUP_PREEMPT</title>
<updated>2011-08-14T10:00:41Z</updated>
<author>
<name>Yong Zhang</name>
<email>yong.zhang0@gmail.com</email>
</author>
<published>2011-07-29T08:20:33Z</published>
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<id>urn:sha1:2c2efaed9bc973e3aeab1385c618017b56c8f6d7</id>
<content type='text'>
Remove the WAKEUP_PREEMPT feature, disabling it doesn't make any sense
and its outlived its use by a long long while.

Signed-off-by: Yong Zhang &lt;yong.zhang0@gmail.com&gt;
Acked-by: Mike Galbraith &lt;efault@gmx.de&gt;
Signed-off-by: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Link: http://lkml.kernel.org/r/20110729082033.GB12106@zhy
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
</content>
</entry>
<entry>
<title>Merge branch 'kvm-updates/3.1' of git://git.kernel.org/pub/scm/virt/kvm/kvm</title>
<updated>2011-07-24T16:07:03Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2011-07-24T16:07:03Z</published>
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<id>urn:sha1:5fabc487c96819dd12ddb9414835d170fd9cd6d5</id>
<content type='text'>
* 'kvm-updates/3.1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (143 commits)
  KVM: IOMMU: Disable device assignment without interrupt remapping
  KVM: MMU: trace mmio page fault
  KVM: MMU: mmio page fault support
  KVM: MMU: reorganize struct kvm_shadow_walk_iterator
  KVM: MMU: lockless walking shadow page table
  KVM: MMU: do not need atomicly to set/clear spte
  KVM: MMU: introduce the rules to modify shadow page table
  KVM: MMU: abstract some functions to handle fault pfn
  KVM: MMU: filter out the mmio pfn from the fault pfn
  KVM: MMU: remove bypass_guest_pf
  KVM: MMU: split kvm_mmu_free_page
  KVM: MMU: count used shadow pages on prepareing path
  KVM: MMU: rename 'pt_write' to 'emulate'
  KVM: MMU: cleanup for FNAME(fetch)
  KVM: MMU: optimize to handle dirty bit
  KVM: MMU: cache mmio info on page fault path
  KVM: x86: introduce vcpu_mmio_gva_to_gpa to cleanup the code
  KVM: MMU: do not update slot bitmap if spte is nonpresent
  KVM: MMU: fix walking shadow page table
  KVM guest: KVM Steal time registration
  ...
</content>
</entry>
<entry>
<title>sched: Allow for overlapping sched_domain spans</title>
<updated>2011-07-20T16:32:41Z</updated>
<author>
<name>Peter Zijlstra</name>
<email>a.p.zijlstra@chello.nl</email>
</author>
<published>2011-07-15T08:35:52Z</published>
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<id>urn:sha1:e3589f6c81e4764d32a25d2a2a0afe54fa344f5c</id>
<content type='text'>
Allow for sched_domain spans that overlap by giving such domains their
own sched_group list instead of sharing the sched_groups amongst
each-other.

This is needed for machines with more than 16 nodes, because
sched_domain_node_span() will generate a node mask from the
16 nearest nodes without regard if these masks have any overlap.

Currently sched_domains have a sched_group that maps to their child
sched_domain span, and since there is no overlap we share the
sched_group between the sched_domains of the various CPUs. If however
there is overlap, we would need to link the sched_group list in
different ways for each cpu, and hence sharing isn't possible.

In order to solve this, allocate private sched_groups for each CPU's
sched_domain but have the sched_groups share a sched_group_power
structure such that we can uniquely track the power.

Reported-and-tested-by: Anton Blanchard &lt;anton@samba.org&gt;
Signed-off-by: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Link: http://lkml.kernel.org/n/tip-08bxqw9wis3qti9u5inifh3y@git.kernel.org
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
</content>
</entry>
<entry>
<title>sched: adjust scheduler cpu power for stolen time</title>
<updated>2011-07-14T09:59:47Z</updated>
<author>
<name>Glauber Costa</name>
<email>glommer@redhat.com</email>
</author>
<published>2011-07-11T19:28:18Z</published>
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<id>urn:sha1:095c0aa83e52d6c3dd7168610746703921f570af</id>
<content type='text'>
This patch makes update_rq_clock() aware of steal time.
The mechanism of operation is not different from irq_time,
and follows the same principles. This lives in a CONFIG
option itself, and can be compiled out independently of
the rest of steal time reporting. The effect of disabling it
is that the scheduler will still report steal time (that cannot be
disabled), but won't use this information for cpu power adjustments.

Everytime update_rq_clock_task() is invoked, we query information
about how much time was stolen since last call, and feed it into
sched_rt_avg_update().

Although steal time reporting in account_process_tick() keeps
track of the last time we read the steal clock, in prev_steal_time,
this patch do it independently using another field,
prev_steal_time_rq. This is because otherwise, information about time
accounted in update_process_tick() would never reach us in update_rq_clock().

Signed-off-by: Glauber Costa &lt;glommer@redhat.com&gt;
Acked-by: Rik van Riel &lt;riel@redhat.com&gt;
Acked-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Tested-by: Eric B Munson &lt;emunson@mgebm.net&gt;
CC: Jeremy Fitzhardinge &lt;jeremy.fitzhardinge@citrix.com&gt;
CC: Anthony Liguori &lt;aliguori@us.ibm.com&gt;
Signed-off-by: Avi Kivity &lt;avi@redhat.com&gt;
</content>
</entry>
<entry>
<title>sched: Move the second half of ttwu() to the remote cpu</title>
<updated>2011-04-14T06:52:41Z</updated>
<author>
<name>Peter Zijlstra</name>
<email>a.p.zijlstra@chello.nl</email>
</author>
<published>2011-04-05T15:23:58Z</published>
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<id>urn:sha1:317f394160e9beb97d19a84c39b7e5eb3d7815a8</id>
<content type='text'>
Now that we've removed the rq-&gt;lock requirement from the first part of
ttwu() and can compute placement without holding any rq-&gt;lock, ensure
we execute the second half of ttwu() on the actual cpu we want the
task to run on.

This avoids having to take rq-&gt;lock and doing the task enqueue
remotely, saving lots on cacheline transfers.

As measured using: http://oss.oracle.com/~mason/sembench.c

  $ for i in /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor ; do echo performance &gt; $i; done
  $ echo 4096 32000 64 128 &gt; /proc/sys/kernel/sem
  $ ./sembench -t 2048 -w 1900 -o 0

  unpatched: run time 30 seconds 647278 worker burns per second
  patched:   run time 30 seconds 816715 worker burns per second

Reviewed-by: Frank Rowand &lt;frank.rowand@am.sony.com&gt;
Cc: Mike Galbraith &lt;efault@gmx.de&gt;
Cc: Nick Piggin &lt;npiggin@kernel.dk&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
Signed-off-by: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Link: http://lkml.kernel.org/r/20110405152729.515897185@chello.nl
</content>
</entry>
<entry>
<title>sched: Rewrite tg_shares_up)</title>
<updated>2010-11-18T12:27:46Z</updated>
<author>
<name>Peter Zijlstra</name>
<email>a.p.zijlstra@chello.nl</email>
</author>
<published>2010-11-15T23:47:00Z</published>
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<id>urn:sha1:2069dd75c7d0f49355939e5586daf5a9ab216db7</id>
<content type='text'>
By tracking a per-cpu load-avg for each cfs_rq and folding it into a
global task_group load on each tick we can rework tg_shares_up to be
strictly per-cpu.

This should improve cpu-cgroup performance for smp systems
significantly.

[ Paul: changed to use queueing cfs_rq + bug fixes ]

Signed-off-by: Paul Turner &lt;pjt@google.com&gt;
Signed-off-by: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
LKML-Reference: &lt;20101115234937.580480400@google.com&gt;
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
</content>
</entry>
<entry>
<title>sched: Remove irq time from available CPU power</title>
<updated>2010-10-18T18:52:27Z</updated>
<author>
<name>Venkatesh Pallipadi</name>
<email>venki@google.com</email>
</author>
<published>2010-10-05T00:03:22Z</published>
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<id>urn:sha1:aa483808516ca5cacfa0e5849691f64fec25828e</id>
<content type='text'>
The idea was suggested by Peter Zijlstra here:

  http://marc.info/?l=linux-kernel&amp;m=127476934517534&amp;w=2

irq time is technically not available to the tasks running on the CPU.
This patch removes irq time from CPU power piggybacking on
sched_rt_avg_update().

Tested this by keeping CPU X busy with a network intensive task having 75%
oa a single CPU irq processing (hard+soft) on a 4-way system. And start seven
cycle soakers on the system. Without this change, there will be two tasks on
each CPU. With this change, there is a single task on irq busy CPU X and
remaining 7 tasks are spread around among other 3 CPUs.

Signed-off-by: Venkatesh Pallipadi &lt;venki@google.com&gt;
Signed-off-by: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
LKML-Reference: &lt;1286237003-12406-8-git-send-email-venki@google.com&gt;
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
</content>
</entry>
<entry>
<title>sched: Remove ASYM_GRAN feature</title>
<updated>2010-03-11T17:32:53Z</updated>
<author>
<name>Mike Galbraith</name>
<email>efault@gmx.de</email>
</author>
<published>2010-03-11T16:17:04Z</published>
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<id>urn:sha1:13814d42e45dfbe845a0bbe5184565d9236896ae</id>
<content type='text'>
This features has been enabled for quite a while, after testing showed that
easing preemption for light tasks was harmful to high priority threads.

Remove the feature flag.

Signed-off-by: Mike Galbraith &lt;efault@gmx.de&gt;
Signed-off-by: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
LKML-Reference: &lt;1268301675.6785.44.camel@marge.simson.net&gt;
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
</content>
</entry>
<entry>
<title>sched: Remove SYNC_WAKEUPS feature</title>
<updated>2010-03-11T17:32:53Z</updated>
<author>
<name>Mike Galbraith</name>
<email>efault@gmx.de</email>
</author>
<published>2010-03-11T16:16:43Z</published>
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<id>urn:sha1:c6ee36c423c3ed1fb86bb3eabba9fc256a300d16</id>
<content type='text'>
Sync wakeups are critical functionality with a long history.  Remove it, we don't
need the branch or icache footprint.

Signed-off-by: Mike Galbraith &lt;efault@gmx.de&gt;
Signed-off-by: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
LKML-Reference: &lt;1268301817.6785.47.camel@marge.simson.net&gt;
Signed-off-by: Ingo Molnar &lt;mingo@elte.hu&gt;
</content>
</entry>
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